this is due soon ill appricate it precalculus

Question

If ,

then =   

 =   Give exact values.

 No decimals allowed!

Answer 1

Since π/4 is 45 degrees, we know that 7π/4 is 315 degrees, which puts it in the 4th quadrant. That means that the cosine is positive, the sine is negative in that quadrant. 45 degrees is a special angle; the ratios of the sides of that triangle would be 1-1-√2:

Cosine of 7π/4 would be 1/√2 or √2/2

Sine of 7π/4 would be -1/√2 or -√2/2

Answer 2

sin(theta) = -(1/2)sqr2

cos(theta) = (1/2)sqr2